Fix arguments' mess with init_http_request

* add named argument byte_range to HttpUrl
* fix arguments order for init_http_request

Change-Id: I6281951f636e8684385ca9f4448d118816aec7b9
Closes-Bug: #1536923

fuel_agent/tests/test_artifact_utils.py

@@ -87,6 +87,22 @@ class TestHttpUrl(unittest2.TestCase):
         for data in enumerate(httpurl):
             self.assertEqual(content[data[0]], data[1])
 
+    @mock.patch.object(utils, 'init_http_request')
+    def test_httpurl_next_slow_connection(self, mock_req):
+        url = "http://fake_url"
+        content = ['fake content #1', '', 'fake content #2']
+        req_mock = mock.Mock(headers={'content-length': 30})
+        req_mock.raw.read.side_effect = content
+        mock_req.return_value = req_mock
+        http_url = au.HttpUrl(url)
+
+        for data in content:
+            if data:
+                self.assertEqual(data, next(http_url))
+        expected_calls = [mock.call(url),
+                          mock.call(url, byte_range=len(content[0]))]
+        self.assertEqual(expected_calls, mock_req.call_args_list)
+
 
 class TestGunzipStream(unittest2.TestCase):
     def test_gunzip_stream_next(self):

fuel_agent/utils/artifact.py

@@ -110,7 +110,7 @@ class HttpUrl(Target):
             except Exception as exc:
                 LOG.exception(exc)
                 self.response_obj = utils.init_http_request(
-                    self.url, self.processed_bytes)
+                    self.url, byte_range=self.processed_bytes)
                 continue
             else:
                 self.processed_bytes += len(data)

fuel_agent/utils/utils.py

@@ -222,7 +222,7 @@ def should_bypass_proxy(url, noproxy_addrs):
     return False
 
 
-def init_http_request(url, proxies=None, noproxy_addrs=None, byte_range=0):
+def init_http_request(url, byte_range=0, proxies=None, noproxy_addrs=None):
     LOG.debug("Trying to initialize http request object %s, byte range: %s",
               url, byte_range)
     if should_bypass_proxy(url, noproxy_addrs):